mephalan chemically alters through alkylation
of the DNA nucleotide guanine and causes linkages between strands of DNA this chemical
alteration inhibits DNA synthesis and RNA synthesis.

Mechanism
of action of cytarabine

Cytarabine acts through direct DNA damage
and incorporation into DNA. Cytarabine is cytotoxic to a wide variety of
proliferating mammalian cells in culture. It exhibits cell phase specificity,
primarily killing cells undergoing DNA synthesis (S-phase) and under certain
conditions blocking the progression of cells from the G1 phase to the S-phase.

mechanism of action of Gemcitabine

Gemcitabine
inhibits thymidylate synthetase, leading to inhibition of DNA synthesis and cell death.

2. PRINCIPLE
OF DRUG RESISTANCE

– Pharmacokinetics /pharmacodynamics factor

– mutations

– Gene regulations

– Generation or use of alternative biochemical pathways

– Drug misuse

Gene regulations
is the most essential of all.

it is a process of ensuring that appropriate genes
are expressed at the appropriate time,gene regulations can be downregulated or upregulated,in
the presence of organism, it make use of this approach if gene is becoming toxic
it could be overexpressed resistance gene
that will encourage them to quickly remove the offending agent from them and then continue to live even in the
presence of the require concentration of the drug.

3. CONTROL OF INFECTION

Food is any substance consumed to provide nutritional
support for an organism,it is usually of plant or animal origin and contain essential
nutrients such as carbonhydrate,fats,proteins,vitamin or minerals.

INFECTION CONTROL

infection control can be define as the discipline involve with preventing
health care associated disease.

FOOD INFECTION CONTROL

food
infection control addresses factors related to spread of infections resulting from
outbreak of food borne disease,everyone needs skills and knowledge in food handling,safety
and should be able to identify and prevent hazard.Many illnesses are due to food
borne diseases which is as a result of ingesting contaminated food or water.

In America today,government inspection of raw food
doesn’t control microbiological contamination,this means that there are contamination
by bacteria,viruses,fungal,toxins and parasites in all types of food to include
meat,poultry,fish,dried foods,fruits and vegetables.Depending on the food source
and the ethics of growers,harvesters,producers and suppliers.

people who
prepare food are another major hazard,when people feel well and have no symptoms
of illnesses,thay can be excreting millions of pathogens per gram in their faeces
and urine.

According to WHO,there are five keys to safer food

– keep
food clean

– separate
raw and cooked food

– cook
food thoroughly

– keep
food at safe temperature

– use
safe water and raw material.

food borne illnesses usually arises from improper
handling,preparation or food storage. Good hygienes practices before,during and
after,food preparation can reduce the chances of contracting an illness.

There is
a consensus in the public health community that regular hand washing is one of the
most important and effective defences against the spread of foodborne illnesses.The
action of monitoring food to ensure that it will not cause foodborne illnesses is
known as food safety.

Hence a safer food is a good measure to control
food borne illnesses and infection which can be hazardous to our health and well-being.

In conclusion,according
to WHO food is safe for consumption and as an infection control when the following
are carried out.

– keeping
of environment clean: This includes the food storage environment which must be kept clean and free of
pesticides which can cause food poisioning an affect individuals state of health
when the food is made for consumption.

– separate
raw and cooked food: this is because there are some microbiological substances that
are present in raw materials which makes it a contaminated ones,such that when one
touches raw materials and the uses the same hand to touch cooked food,there are
enough pathogens that will be transferred
to the cooked food which can result to illness when one consume the food.

– Cooked food thoroughly : food must be well
cooked,half cooked food is very hazardous to individual health e.g meat an raw egg
must be properly cook in other to make it safer for consumption.

– keep food at safe temperature : storing food
in the refrigerator is used to control the growth of pathogens.Hot foods that needs
to be refrigerate must be allow to cool for at least 30 minutes.

-using of safe water and raw materials :according
to WHO,a safe water safe life which means,clean and uncontaminated water and raw
materials must be use to prepare food.

Hence,proper food handling,storage,safety,hygiene
and preparation is a means of infection control.